java ipv6检测工具

以下是一个Java的IPv6检测工具的示例代码：

import java.net.InetAddress;
import java.net.UnknownHostException;

public class IPv6Checker {
    public static void main(String[] args) {
        String ip = "abcd::abcd:abcd:abcd:abcd";
        try {
            InetAddress address = InetAddress.getByName(ip);
            if (address instanceof java.net.Inet6Address) {
                System.out.println(ip + " is a valid IPv6 address.");
            } else {
                System.out.println(ip + " is not a valid IPv6 address.");
            }
        } catch (UnknownHostException e) {
            System.out.println("Invalid IP address: " + ip);
        }
    }
}

该代码使用`InetAddress`类的`getByName`方法将IP地址转换为`InetAddress`对象，然后通过判断该对象是否为`Inet6Address`的实例来确定是否为有效的IPv6地址。